The glassy-winged sharpshooter (GWSS) was introduced into California in the early 1990's from the Southeastern US. The GWSS feeds on 250+ species of plants, and threatens grape, almond, peach, and oleander production because it vectors the bacteria that causes the deadly Pierce's disease. Each time the GWSS moves to a new host plant, the possibility of its acquiring and transmitting the Pierce's disease bacterium increases. We utilized caged artificial habitats to determine the effects of both plant species availability and predator pressure on GWSS interplant movement. GWSS were provided with either a monoculture of bean plants or polyculture of bean, sorghum, walnut, tree tobacco, sunflower, and citrus. The plant availability was combined with the presence/absence of spiders in a 2x2 factorial design. Individual GWSS were marked and their location and feeding noted every half hour for 13 hours of daylight. Although the GWSS fed on all plant species, they showed a clear preference for bean, sunflower, and citrus. They appeared to leave a host plant due either to inadequate nutrients or to satiation. Spiders that were not actively moving had little effect on the GWSS' behavior, and the GWSS did not respond to the presence of non-foraging spiders. Thus, nutritional effects drive GWSS foraging behavior. Spiders can reduce GWSS numbers, but do little to affect the GWSS’ movement between plants.